The present invention relates generally to an interlock system for multi-drawer cabinets and specifically to an interlock system in which one of the drawers is in the open position, none of the remaining drawers can be moved to the open position.
The primary reason for preventing the opening of more than one drawer of the multi-draw cabinet at any one time, is to prevent the cabinet from tipping over due to an unbalanced condition which is created by the weight of material in two or more open drawers. When two or more drawers are fully opened at the same time, the weight of the material in the drawers causes the center of gravity of the cabinet to shift forwardly. If the center of gravity is forward of the base of the cabinet, the cabinet tips forwardly toward the individual who is working with the cabinet. This condition can cause serious injury to the individual. Many types of interlock systems have been suggested in the past. However, these devices have not been completely satisfactory with respect to operation, costs, and objectionable noise. My prior U.S. Pat. No. 4,711,505 represents a substantial improvement in the art of interlocking systems for cabinets. There is a latching module which is associated with each drawer of the cabinet. A line of discreet elements such as balls extend between adjacent modules which are guided in a track that extends between the adjacent modules. The balls are aligned so that an actuator ball impinges between two adjacent discreet elements or balls in the track. When a drawer is opened, an actuator which is associated with the drawer causes the actuator ball to move between two of the discreet elements in the track and displace the discreet elements along the axis of the track. This displacement shifts the alignment of the discreet elements with respect to other actuator balls so that each of the other actuator balls impinges directly on a discreet element rather than between two adjacent discreet elements in the track. Although this system offers many advantages over other prior art devices with respect to operation and versatility, there are certain objectionable characteristics. For example, the string of discreet elements which extend between two actuators must be confined and guided and they require precise positioning in order for the system to function properly. These and other difficulties experienced with the prior art interlock devices have been obviated by the present invention.
It is, therefore, a principle object of the invention to provide an interlock system for multi-draw cabinets which includes a latching module for each draw and a single rigid connector between adjacent modules which does not require guides and tracks between adjacent modules.
Another object of this invention is the provision of an interlock system for multi-draw cabinets which includes a latching module for each drawer and a single locking module which operates in conjunction with the latching modules for preventing the opening of all drawers of the cabinet when the locking module is in the locked position.
A further object of the present invention is the provision of an interlock system for multi-draw cabinets which utilizes a latching module for each drawer in which each module is made up of several components which can be combined in a plurality of ways to vary the function of the module, such as left and right hand operation.
It is another object of the present invention to provide an interlock system for a multi-draw cabinet which utilizes a plurality of latching modules in a locking module wherein each module comprises several components and at least some of the components of the latching module are interchangeable with at least some of the components of the locking module.
A still further object of the invention is the provision of an interlock system for multi-draw cabinets which is adaptable to a wide range of cabinets while utilizing relatively few basic components.
It is a further object of the invention to provide an interlock system for a multi-drawer cabinet which comprises relatively few basic components which are relatively simple in construction and relatively easy to install in a cabinet.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.